The Porsche Panamera has helped to pave the way to a new era for the Stuttgart brand over its 15-year life to date. Now in its third generation, this sports-luxury saloon has climbed to the very top of the performance car market with a sublime mix of quality, comfort and speed.

And in every regard, it would seem that Porsche has continued to develop what was already a winning formula into what you could argue is its best...